2+3+7+8=20
2 x 3+7+ 8= 21
2 x 7 + 3+ 8= 25
8 x 2 + 7 + 3= 26
3 x 7 +8 - 2= 27
8 x 3 + 7 - 2= 29
8 x 7 ÷ 2 + 3= 31
7 x 2 x 3 -8 = 34
There is a couple, but i am not doing all of them
I hope this helps anyway :).
18 kg of 15% copper and 72 kg of 60% copper should be combined by the metalworker to create 90 kg of 51% copper alloy.
<u>Step-by-step explanation:</u>
Let x = kg of 15% copper alloy
Let y = kg of 60% copper alloy
Since we need to create 90 kg of alloy we know:
x + y = 90
51% of 90 kg = 45.9 kg of copper
So we're interested in creating 45.9 kg of copper
We need some amount of 15% copper and some amount of 60% copper to create 45.9 kg of copper:
0.15x + 0.60y = 45.9
but
x + y = 90
x= 90 - y
substituting that value in for x
0.15(90 - y) + 0.60y = 45.9
13.5 - 0.15y + 0.60y = 45.9
0.45y = 32.4
y = 72
Substituting this y value to solve for x gives:
x + y = 90
x= 90-72
x=18
Therefore, in order to create 90kg of 51% alloy, we'd need 18 kg of 15% copper and 72 kg of 60% copper.
Here, we can set up a proportion:
34 ÷ 3/4 = ? ÷ 1
34*1 = 34
34÷3/4 = the time needed to build one toyboat
34/3/4 = 45.3333333333
45.3 repeating is not a whole number, so we need to approximate.
45 is the closest whole number,
So.. a machine can paint 45 toy boats per hour.
I really hope that helped! :)
Answer:
Step-by-step explanation:
hmmmmmmmmmm
Answer
12855.04 ft³
Step-by-step explanation:
regular Octagon consists of 8 congruent triangles
B = (13.28 x 11) / 2 x 8=584.32
V = BH = 584.32 x 22 = 12855.04
